April is the month when spring definitely starts to spring, the month when the countryside finally loses its winter look and bursts into life. Suddenly, everything is trying to flower and blossom at once, leaves return to the trees, and grass and verge plants grows green and tall.

At the start of the month, woodland and fields still have a tired, worn-out look about them. By the end, all is lush and optimistic, but not yet straggly and overgrown as it can become later in May. Throughout April there is some new sign of spring almost every time you step out into the countryside. For the nature lover it is the most exciting time of the year.

Flowers, flowers everywhere

April is the first of four glorious months for wildflowers, though of all the four, April is perhaps the best for the way in which flowers just pop up everywhere, a nice surprise after the drabness of winter. There are three main locations to spot them: on woodland floors, on field and path verges, and in front gardens, where wild species tend to be indulged by gardeners this time of year.

This is a time of year when hotter or colder weather than usual can have big effects, however. In 2007 and 2011 a sunny March and temperatures into the mid 20s in April made many events described on this and other April pages happen a week to ten days earlier. That was also true in 2014 after a mild winter. By contrast in 2006 a cold March made everything later by a similiar amount. Even later was 2013, when a bitterly cold March left the countryside at the start of April looking little different from mid February. It was not until the second week that year that spring started to any degree and all April events were two to three weeks late.

Other unusual years include 2008, when five inches of snow on 6 April brought what had until then been an early spring to a sudden halt, causing a ten day hiatus before everything returned to the normal schedule. In 2012 a hot March followed by an unusually cool April also caused a lot of confusion, with some flowers and blossom coming out early and then going into a kind of suspended animation, and others coming out late.

2016 was also a curious mixture of early and late: an exceptionally mild November and December 2015 caused some spring events to start as early as January, but a relatively cold February and March then followed. April also saw below average temperatures and ended with a week of wintry northern winds. All of this delayed the onset of spring by two to three weeks, pushing many second half of April flowers into May. However in 2010, despite the coldest winter in 30 years, most flowers and blossom were on time.

Woodland flowers

A unique feature of April – and indeed of the temperate zone of the northern hemisphere – are the flowers that carpet woodland floors. These flowers are specially adapted to appear before the leaves come out on the trees and so grow in places that no other flora can. The most famous one – the bluebell – seems to leave things right till the last minute, only flowering once the beech and oak woods its favours are in full leaf.

At the start of the month the star attraction is the wood anemone – quite literally, as they open to beautiful white stars on warm days, closing to demure bells at night or on cooler days. This simple plant, consisting of a stalk, three leaves and one flower, is at its best in the first two weeks of the month, usually lasting just long enough to overlap with early bluebells. A few wood anemones can be found right up to the end of April, however, and in 2012 they were even at their best in the third week in some places. In 2013 they did not start to appear until the second week of April, were not full out till the third week, and lasted in many places until the last week of May.

In 2016 wood anemone were not out in any quantity till the very end of March and many were still quite small at this time. They then lasted throughout April with some surviving into early May, but many woods saw less than half the normal number of flowers. In 2018 flowering was more or less as normal but was brought to a sudden close by a very hot third week of the month, going from being full out to largely over in just seven days.

Isolated bluebell flowers can be found as early as the first week of April, but typically they start to come out in force mid month and are best in the last week in April and the first week in May. There are variations in this from year to year and place to place, however. In 2014 bluebells were out in force as early as the second week and by the end of the month they were fading everywhere but in the Chilterns. In the hot and dry springs of 2007 and 2011 bluebells came out at the normal time but were at best at the end of the third week and largely over by the end of the month, perhaps due to the lack of rain.

In 2016, aided by a warm December, many bluebell plants grew early and a scattering of flowers could be seen from the start of March. Some woods were already a third out at the start of April and as much as two thirds by the end of the first week. But the flowers then went on to stick to normal season timings, being full out from mid April to the end of the first week in May. Likewise in 2017 many woods made an early start, with some as much as half out in the first week, but curiously there was then not much advance till mid month and the bluebell season then proceeded pretty much as normal.

In 2012 unusually hot weather brought bluebells out in quantity as early as the last week of March in some locations but the cool, showery weather in April brought everything to a complete halt. By the end of the month most woods were still only 60-70 percent out, which was the best many of them achieved. In 2018 the opposite weather sequence produced the same final effect: March and the first half of April were cold and bluebells had barely started by mid month. But a very hot third week then caused all the leaf foliage to come out at once, shading the bluebells out. Many woods consequently never looked more than half out for the rest of the season.

In other years cold weather in February and March has caused bluebell woods to be barely out by the end of April and to last well into May. That was certainly true in 2005, 2006 and 2013, while in 2010 when they came out in force only in the last week.

In a normal year, wood anemones overlap with bluebells by a week to ten days, making a pretty display when they are present in the same wood. But in 2016 the late flowering of wood anemones meant the two came out concurrently, while in 2018 wood anemones were completely over before the bluebells came out. Equally, normally bluebells coincide with beech leaves appearing, but in 2016 they were well ahead, with beech leaves not out till the first week of May. The same also happened in 2017.

Whatever the year, trying to catch bluebells at their best is always a frustrating business: and one of the most painful experiences is to do a walk past a bluebell wood that is not yet in full bloom or one that is past its peak. At best, all flowers on each stalk are open and each flower is fat, and the woods have a magical blue-purple haze.

Another dramatic woodland display comes towards the end of the month (in places as early as mid month) with the flowering of ramsons (commonly known as wild garlic, though they are in fact only a relative of the variety we eat). Their distinctive smell usually alerts you to their presence before you see their delicate white blooms, carpeting damper woodlands and the shady sides of streams. They tend not to be at their best till the early part of May, however.

You can also find lesser celandines and primroses in woods - sometimes in great profusion (celandines in particular can carpet areas of woodland). These tend to be at their best early in the month but some can be found right till the end. The same is true of violets (usually dog violets, but sometimes sweet violets).

Other woodland plants are harder to spot, though in some cases it is not for want of trying. Dog's mercury covers vast swathes of woodland in April but its flower is so inconspicuous it is rarely noticed. It does, however, provide a welcome dash of green to the woodland floor. There are in fact male and female plants and towards the end of the month the latter are producing tiny green seeds. There is also a fair amount of pendulous sedge, which has long thin leaves like an iris and which produces a yellow tassel of a flower this month - not much noticed, but quite common.

Much more elusive is wood sorrel, which produces white flowers in shy clumps in damp woodland spots. (There often seem to be many more leaves than flowers). It generally goes over towards the end of the month, but survives in some places into May (in 2016 it did not really come out in force until May). Meanwhile woodruff appears in the second half along the edge of woodland paths, with its distinctive spiky ruff of leaves and small white flowers which can produce a surprisingly enchanting effect en masse, though it is usually May before it is at its best.

Even more inconspicuous mat formers include moschatel, also called townhall clock for its tiny four-sided greeny-yellow flowers (like wood anemone, it is an indicator of ancient woodlands), and ivy-leaved speedwell, which has flowers so tiny and so pale they are almost invisible. Also golden saxifrage that forms greeny-yellow patches in damp places. All tend to be seen only in the first two thirds of the month.

Mid month other specialist woodland flowers appear, including goldilocks buttercup - the first buttercup of the year, identifiable by its unusual thin leaves and misshapen petals - and herb robert, which has scattered pink flowers. Look out also for delicate blue wood speedwell. In bluebell woods you can find the unromantically named early purple orchid whose purple or pink spikes make a striking contrast to the sea of blue. Clumps of yellow archangel - a yellow deadnettle - also perform a similar function (note that there are two varieties of this - a native one and a very common garden escapee named "argentatum" whose silver-streaked leaves are evident all winter). So do the delicate double-petalled white stars of stitchwort, better known as a hedgerow plant but also perfectly at home in lighter patches in woods.

Other verge flowers that can also be found in woodlands later in April include ground ivy, bugle, red campion, wavy bittercress and the weird flowers of cuckoo pint. Just possibly cuckoo flower (aka lady's smock) may occur too. Towards the end of the month cow parsley flowers in some woods. Woodland also plays host to stinging nettles, cleavers (aka goosegrass) and wood spurge, the first two of these contributing greatly to thegeneral lushness of the woodland floor, growing from little more than shoots at the start of the month and up to half a metre tall by its end. Bracken likewise uncurls in the second half of the month, spoiling the purity of some bluebell woods.

Rarer flowers that you may see include yellow pimpernel, a ground creeping plant which appears in the second half, and green hellebore, which has green flowers that hang down amidst large leaves (it flowers February to April and so is coming to the end now). In the Chilterns or eastern Weald if you see a pink flower in the second half it may be coralroot - it grows wild only in these two places. In dry woods (for example on sand) lily of the valley may be coming out at the end of the month. At the same time you may also see sanicle in chalk woodland, a rather atypical relative of cow parsley; May is its more usual flowering time, however.